The present invention is directed to an arrangement for exposing semiconductor wafers with synchroton radiation in a lithography equipment, wherein parallel X-rays are guided in a beam tube through a radiation window and impinge on a structured mask and then on a semiconductor wafer to be structured, the mask and the semiconductor wafer are movable in a common plane perpendicular to the direction of radiation in order to sweep an exposure field, which is larger than the impinged area of the X-ray beam defined by the radiation window, and adjustment marks are provided on the mask and on the semiconductor wafer, which are examined by optical devices and are utilized to create control signals for controlling the movement of the mask and semiconductor wafer relative to each other.
An arrangement of this type was disclosed in an article by K. H. Mueller entitled "Overlay Measurements for X-ray Lithography", J. Vac. Sci. Technol. B., Vol. 3, No. 1, Jan/Feb. 1985, pp. 241-244. The radiation window is provided in a wall of an exposure chamber in which either a vacuum or a helium atmosphere of about 50 mbar are built up in order to lead the X-ray beam to the mask and semiconductor combination, which is arranged in the exposure chamber spaced from the window, in a loss-free of fashion as possible. Observation of the adjustment marks applied to the mask and to the semiconductor wafer occurs via a microscope comprising two objectives, which are arranged in the exposure chamber and are pivotable around a stationary axis between the window and mask.
For the purpose of mutual adjustment of the mask and semiconductor wafer, the objectives are pivoted into a working position, which is between the radiation window and the mask, and has the objectives being immediately proceeding a mask in the direction of radiation and aligned with the adjustment marks thereon. After the adjustment, they can be pivoted out of the working position so that the X-ray can have unimpeded access. The exposure of the mask/semiconductor wafer combination then occurs, wherein the latter, in its adjusted position is moved through the beam perpendicular to the beam direction in order to sweep an exposure field, which is larger than the impinging area of the X-ray defined by the radiation window. Given this arrangement, it is necessary to open the exposure chamber when replacing the exposed semiconductor wafer with one to be subsequently exposed or when replacing the employed mask with another mask. After each opening of the exposure chamber, the vacuum or the helium atmosphere must then be reintroduced in order to continue the exposure procedure, and this makes the exposure procedure lengthy and involved. In addition, the objectives of the microscope must be pivoted into the working position for every adjustment procedure and must, in turn, be pivoted out again before the beginning of the following exposure, and this pivoting of the objectives increases the operating outlay and cost.